1. Field of the Invention
The present invention is concerned with improved high temperature superconducting oxides of the HgBaCaCu family which are doped with thallium. These superconducting oxides exhibit high T.sub.c and J.sub.c values and are suitable for use with cryogenic systems operating at about the
2. Description of the Prior Art
The homologous series of superconductors HgBa.sub.2 Ca.sub.n-1 Cu.sub.n O.sub.2n+2+.alpha. has recently been reported. These oxides possess relatively high T.sub.c values on the order of 135K. However, the Hg plane of the resultant crystalline structures is very oxygen deficient, which limits the potential T.sub.c values of this family of superconductors. Moreover, this type of superconducting oxide is very difficult to economically manufacture, owing to the volatility of the Hg present, and the tendency of the oxides to adversely react with water vapor and carbon dioxide during the manufacturing process.
There is accordingly a need in the art for improved Hg-based superconducting oxides which are more readily manufactured and which have a higher oxygen content and T.sub.c values.